Toward the Edge-Cloud Continuum Through the Serverless Workflows

Cloud-edge continuum is a recently recreated term used to refer to solutions that aim at taking advantage of a distributed cloud-edge infrastructure to run applications where they best fit at a given moment, which is dependent on infrastructure system, application, and constraints, eventually adapting that according to a change on those factors. Until now, there not exists a universal approach to build continuum native applications, and therefore different frameworks have been proposed focusing on the context and scenario where they are applied. In this work, we try to provide a reference architecture that allows to build relocable continuum native applications by the use of the function-as-a-service (FaaS) model, adapting the concept of scientific workflow, to build instead FaaS continuum workflows. By doing that, we will introduce a dictionary of terms and architecture guidelines to follow to get a continuum infrastructure. We will validate this work by describing a compliant implementation of this infrastructure called OpenWolf, a recently born open-source project that lets to design FaaS-based workflows for heterogeneous Kubernetes clusters. Moreover, we will also validate this project by designing and testing a continuous learning workflow used to keep security and safety in smart city.